-LRB- CNN -RRB- -- The sagging economy is taking a bite out of federal school-meal subsidies as more students take advantage of free or low-price breakfasts and lunches , nutritionists say in a report released Thursday .

About 425,000 more students are participating in the National School Lunch Program , a group reports .

The School Nutrition Association surveyed more than 130 school nutrition directors from 38 states to produce its report , `` Saved by the Lunch Bell : As Economy Sinks , School Nutrition Program Participation Rises . ''

The nonprofit organization said that about 425,000 more students are participating in the National School Lunch Program and the School Breakfast Program in 2008-09 than in the previous school year .

That represents an average increase of 2.5 percent from 2007-08 , the report says .

These numbers hold true despite a slight decline in the number of students enrolled in public schools this school year , according to the study .

More than three-quarters of the districts surveyed reported a rise in the number of students eating free meals under the U.S. Department of Agriculture program , the report says .

Many of the school district employees who monitor the food programs complain that the federal subsidies fall far short of the rising costs .

According to the association , the estimated average cost to prepare a school meal is $ 2.90 , but the federal reimbursement is $ 2.57 .

School lunch programs are experiencing a potential loss of at least $ 4.5 million per school day , based on 30 million school lunches provided , the group says .

The good news , according to association President Katie Wilson , is that `` this year , when hunger is more common , more students are able to eat a balanced , nutritious meal at school . ''

Meals served under the USDA programs must meet nutrition guidelines based on the Dietary Guidelines for Americans . For lunches , that means no more than 30 percent of calories can come from fat and fewer than 10 percent from saturated fat .

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Number of students eating subsidized meals rises 2.5 percent , nonprofit says

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Use of USDA programs rises even as enrollment falls , report notes

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Schools complain that USDA does n't cover full cost of meals

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School Nutrition Association surveyed 130 school food directors in 38 states